2-nitromethylidene/2-cyanimino/2-nitro-imino-pyrrolidines and piperidines, intermediates, and their use as pesticides

ABSTRACT

Compounds of formula (I), wherein A is an unsubstituted or substituted aromatic or non-aromatic, monocyclic or bicyclic heterocyclic radical wherein a ring nitrogen atom may have been replaced by a group ##STR2## R 1  is hydrogen or C 1  -C 3  alkyl; R 2  is hydrogen or C 1  -C 3  alkyl; R 3  is hydrogen, an unsubstituted or substituted C 1  -C 6  alkyl, C 3  -C 6  cycloalkyl C 2  -C 6  alkenyl or C 2  -C 6  alkynyl group, or C(═O)--R 5 , R 5  is C 1  -C 4  alkyl C 1  -C 4  alkoxy, an unsubstituted or substituted phenyl, phenoxy or benzyloxy group, or N(R 6 ) 2 , each R 6 , independently of the other, is hydrogen, C 1  -C 4  alkyl or unsubstituted or substituted phenyl, X is CH--NO 2 , N--CN or N--NO 2  and n is from 1 to 3, in free form or in salt form, and, where appropriate, tautomers of those compounds and the salts thereof, can be used as agrochemical active ingredients and can be prepared in a manner known per se.

This is a 371 of international application PCT/EP94/00963, filed Mar.26, 1994.

The invention relates to compounds of formula ##STR3## wherein A is anunsubstituted or substituted aromatic or non-aromatic, monocyclic orbicyclic heterocyclic radical wherein a ring nitrogen atom may have beenreplaced by a group ##STR4## R₁ is hydrogen or C₁ -C₃ alkyl; R₂ ishydrogen or C₁ -C₃ alkyl;

R₃ is hydrogen, an unsubstituted or substituted C₁ -C₆ alkyl, C₃ -C₆cycloalkyl, C₂ -C₆ alkenyl or C₂ -C₆ alkynyl group, or C(═O)--R₅,

R₅ is C₁ -C₄ alkyl, C₁ -C₄ alkoxy, an unsubstituted or substitutedphenyl, phenoxy or benzyloxy group, or N(R₆)₂,

each R₆, independently of the other, is hydrogen, C₁ -C₄ alkyl orunsubstituted or substituted phenyl,

X is CH--NO₂, N--CN or N--NO₂ and

n is from 1 to 3,

in free form or in salt form, where appropriate to tautomers of thosecompounds and to the salts thereof, to processes for the preparation ofthose compounds and tautomers and to the use thereof, to pesticidalcompositions comprising an active ingredient selected from thosecompounds and tautomers, to a process for the preparation of thosecompositions and to the use thereof, to plant propagation materialtreated with those compositions, to a method of controlling pests, tointermediates and, where appropriate, the tautomers thereof, in eachcase in free form or in salt form, to processes for the preparation ofthose active ingredients and to processes for the preparation of thoseintermediates and the tautomers thereof.

The invention relates especially to compounds of formula I wherein

A is an unsubstituted or mono- to tetra-substituted aromatic ornon-aromatic, mono-cyclic or bicyclic heterocyclic radical wherein aring nitrogen atom may have been replaced by a group ##STR5## andwherein one or two of the substituents of A may be selected from thegroup consisting of C₁ -C₃ alkyl, halo-C₁ -C₃ alkyl, cyclopropyl,halocyclopropyl, C₂ -C₃ alkenyl, C₂ -C₃ alkynyl, halo-C₂ -C₃ alkenyl,halo-C₂ -C₃ alknyl, hydroxy, mercapto, halo-C₁ -C₃ alkoxy, C₁ -C₃alkylthio, halo-C₁ -C₃ alkylthio, allyloxy, propargyloxy, allylthio,propargylthio, haloallyloxy, halo-allylthio, cyano and nitro, and fromone to four of the substituents of A may be selected from the groupconsisting of C₁ -C₃ alkyl, C₁ -C₃ alkoxy and halogen;

R₁ is hydrogen or C₁ -C₃ alkyl;

R₂ is hydrogen or C₁ -C₃ alkyl;

R₃ is hydrogen, C₁ -C₆ alkyl, halo-C₁ -C₆ alkyl, C₁ -C₆ alkoxy-C₁ -C₆alkyl, C₁ -C₆ alkyl-thio-C₁ -C₆ alkyl, phenoxy-C₁ -C₆ alkyl,phenylthio-C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl-C₁ -C₆ alkyl, benzyloxy-C₁-C₆ alkyl, di(C₁ -C₄ alkyl)amino-C₁ G₆ alkyl, cyano-C₁ -C₆ alkyl, C₁ -C₄alkylcarbonyl-C₁ -C₆ alkyl, C₁ -C₄ alkoxycarbonyl-C₁ -C₆ alkyl, C₃ -C₆cycloalkyl, halo-C₃ -C₆ cycloalkyl, C₂ -C₆ alkenyl, halo-C₂ -C₆ alkenyl,C₂ -C₆ alkynyl, halo-C₂ -C₆ alkynyl or C(═O)--R₅,

R₅ is C₁ -C₄ alkyl, C₁ -C₄ alkoxy, phenyl, phenoxy or benzyloxy, orphenyl, phenoxy or benzyloxy substituted by from one to threesubstituents selected from the group consisting of halogen, C₁ -C₄alkyl, halo-C₁ -C₄ alkyl, C₁ -C₄ alkoxy, nitro and cyano, or is N(R₆)₂,

each R₆, independently of the other, is hydrogen, C₁ -C₄ alkyl orphenyl, or phenyl substituted by from one to three substituents selectedfrom the group consisting of halogen, C₁ -C₄ alkyl, halo-C₁ -C₄ alkyl,C₁ -C₄ alkoxy, nitro and cyano,

X is CH--NO₂, N--CN or N--NO₂ and

n is from 1 to 3,

and the tautomers thereof, in each case in free form or in salt form.

Certain 3-substituted 2-nitromethylidene-piperidines and2-nitromethylidene-pyrrolidines are proposed in the literature asarthropodicidal active ingredients in pesticides. The biologicalproperties of those known compounds are not, however, fully satisfactoryin the area of pest control and there is therefore a need to providefurther compounds having pest-control properties, especially forcontrolling insects. That problem is solved according to the inventionby the provision of the present compounds of formula I.

Some of the compounds of formula I can be in the form of tautomers. Thatrelates, for example, to the heterocyclic radicals A that aresubstituted by a hydroxy group or by a mercapto group wherein, dependingon the structure, the hydroxy or the oxo form, or the mercapto or thethioxo form, respectively, may be present, or the two tautomeric formsmay be present alongside one another.

Compounds of formula I having at least one basic centre are capable offorming acid addition salts. Those salts are formed, for example, withstrong inorganic acids, such as mineral acids, for example perchloricacid, sulfuric acid, nitric acid, nitrous acid, a phosphoric acid or ahydrohalic acid, with strong organic carboxylic acids, such asunsubstituted or substituted, for example halo-substituted, C₁ -C₄alkanecarboxylic acids, for example acetic acid, or saturated orunsaturated dicarboxylic acids, for example oxalic, malonic, succinic,maleic, fumaric or phthalic acid, or hydroxycarboxylic acids, forexample ascorbic, lactic, malic, tartaric or citric acid, or benzoicacid, or with organic sulfonic acids, such as unsubstituted orsubstituted, for example halo-substituted, C₁ -C₄ alkanesulfonic orarylsulfonic acids, for example methanesulfonic or p-toluene-sulfonicacid. Furthermore, compounds of formula I having at least one acidicgroup are capable of forming salts with bases. Suitable salts with basesare, for example, metal salts, such as alkali metal or alkaline earthmetal salts, for example sodium, potassium or magnesium salts, or saltswith ammonia or an organic amine, such as morpholine, piperidine,pyrrolidine, a mono-, di- or tri-lower alkylamine, for exampleethylamine, diethylamine, triethylamine or dimethylpropylamine, or amono-, di- or tri-hydroxy-lower alkylamine, for example mono-, di- ortri-ethanolamine. Where appropriate, corresponding internal salts may beformed. Preference is given within the scope of the invention toagro-chemically acceptable salts, but salts that have disadvantages foragrochemical purposes are also included; they are used, for example, inthe isolation or purification of free compounds of formula I or theagrochemically acceptable salts thereof. Hereinbefore and hereinafter,the expression "compound(s) of formula I" thus always also includes thesalts of those compounds, their tautomers and the salts of thetautomers.

Suitable as heteroatoms in the basic ring structure of the heterocyclicradical A are any elements of the Periodic Table that are capable offorming at least two covalent bonds, but preference is given to oxygen,nitrogen and sulfur, especially nitrogen and sulfur, more speciallynitrogen.

Halogen--per se and as a structural element of other groups andcompounds, such as haloalkyl, haloalkylthio, haloalkoxy,halocyclopropyl, haloalkenyl, haloalkynyl, haloallyloxy andhaloallylthio--is fluorine, chlorine, bromine or iodine, especiallyfluorine, chlorine or bromine, more especially fluorine or chlorine andmost especially chlorine.

Unless otherwise defamed, carbon-containing groups and compounds eachcontain from 1 up to and including 6, preferably from 1 up to andincluding 3, more especially 1 or 2, carbon atoms.

Cycloalkyl is cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl,preferably cyclopropyl.

Alkyl--as a group per se and as a structural element of other groups andcompounds, such as haloalkyl, alkoxy, haloalkoxy, alkylthio andhaloalkylthio--in each case taking due account of the number of carbonatoms in the group or compound in question--is either straight-chained,i.e. methyl, ethyl, propyl, butyl, pentyl or hexyl, or branched, e.g.isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl orisohexyl.

Alkenyl, haloalkenyl, alkynyl and haloalkynyl are straight-chained orbranched and each contain two or preferably one unsaturatedcarbon-carbon bond(s). The double or triple bonds of those substituentsare separated from the remainder of the compound of formula I preferablyby at least one saturated carbon atom. The following may be mentioned byway of example: allyl, methallyl, but-2-enyl, but-3-enyl, propargyl,but-2-ynyl and but-3-ynyl.

Halo-substituted carbon-containing groups and compounds, such ashaloalkyl, haloalkylthio, haloalkoxy, halocycloalkyl, haloalkenyl,haloalkynyl, haloallyloxy and haloalkylthio, may be partiallyhalogenated or perhalogenated, it being possible in the case ofpolyhalogenation for the halogen substituents to be identical ordifferent Examples of haloalkyl--as a group per se and as a structuralelement of other groups and compounds, such as haloalkylthio andhaloalkoxy--are methyl mono- to tri-substituted by fluorine, chlorineand/or by bromine, such as CHF₂ or CF₃ ; ethyl mono- topenta-substituted by fluorine, chlorine and/or by bromine, such as CH₂CF₃, CF₂ CF₃, CF₂ CCl₃, CF₂ CHCl₂, CF₂ CHF₂, CF₂ CFCl₂, CF₂ CHBr₂, CF₂CHClF, CF₂ CHBrF or CClFCHClF; and propyl or isopropyl mono- tohepta-substituted by fluorine, chlorine and/or by bromine, such as CH₂CHBrCH₂ Br, CF₂ CHFCF₃, CH₂ CF₂ CF₃, CF₂ CF₂ CF₃ or CH(CF₃)₂. Examplesof haloalkenyl are 2,2-difluoroethen-1-yl, 2,2-dichloroethen-1-yl,2-chloroprop-2-en-1-yl, 2,3-dichloroprop-2-en-1-yl and2,3-dibromoprop-2-en-1-yl. Examples of haloalkynyl are2-chloroprop-2-yn-1-yl, 2,3-dichloroprop-2-yn-1-yl and2,3-dibromoprop-2-yn-1-yl. Examples of halocyclopropyl are2-chlorocyclopropyl, 2,2-difluorocyclopropyl and2-chloro-2-fluoro-cyclopropyl. Examples of haloallyloxy are2-chloroprop-2-en-1-yloxy, 2,3-dichloroprop-2-en-1-yloxy and2,3-dibromoprop-2-en-1-yloxy. Examples of haloallylthio are2-chloroprop-2-en-1-ylthio, 2,3-dichloroprop-2-en-1-ylthio and2,3-dibromoprop-2-en-1-ylthio.

C₁ -C₆ Alkoxy-C₁ -C₆ alkyl, phenoxy-C₁ -C₆ alyl, phenylthio-C₁ -C₆alkyl, C₃ -C₆ cycloalyl-C₁ -C₆ alkyl, benzyloxy-C₁ -C₆ alkyl, di(C₁ -C₄alkyl)amino-C₁ -C₆ alkyl, cyano-C₁ -C₆ alkyl, C₁ -C₄ alkylcarbonyl-C₁-C₆ alkyl, C₁ -C₄ alkoxycarbonyl-C₁ -C₆ alkyl and C₁ -C₆ alkylthio-C₁-C₆ alkyl are alkyl groups mono-substituted by alkoxy, phenoxy,phenylthio, C₃ -C₆ cycloalkyl, benzyloxy, di(C₁ -C₄ alkyl)amino, cyano,C₁ -C₄ alkylcarbonyl, C₁ -C₄ alkoxycarbonyl or by alkylthio, it beingpossible for the two carbon chains each independently of the other to bestraight or branched. Examples are methoxymethyl, 2-methoxyethyl,ethoxymethyl, 2-isopropoxyethyl, 2-propoxypropyl, 4-methoxybut-2-yl,2-methylthioethyl, ethylthiomethyl, phenoxymethyl, 2-cyanoethyLdimethylaminomethyl and cyclopropylmethyl.

Preferred embodiments within the scope of the invention are:

(1) A compound of formula I wherein

A is an unsubstituted or mono- to tetra-substituted aromatic ornon-aromatic, mono-cyclic or bicyclic heterocyclic radical, wherein oneor two of the substituents of A may be selected from the groupconsisting of halo-C₁ -C₃ alkyl, cyclopropyl, halocyclopropyl, C₂ -C₃alkenyl, C₂ -C₃ alkynyl, halo-C₂ -C₃ alkenyl, halo-C₂ -C₃ alkynyl,halo-C₁ -C₃ alkoxy, C₁ -C₃ alkylthio, halo-C₁ -C₃ alkylthio, allyloxy,propargyloxy, allylthio, propargylthio, haloallyloxy, haloallylthio,cyano and nitro, and from one to four of the substituents of A may beselected from the group consisting of C₁ -C₃ alkyl, C₁ -C₃ alkoxy andhalogen;

R₁ is hydrogen or C₁ -C₃ alkyl;

R₂ is hydrogen or C₁ -C₃ alkyl;

R₃ is hydrogen, C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₂ -C₆ alkenyl or C₂-C₆ alkynyl;

X is CH--NO₂ or N--CN, and

n is from 1 to 3;

(2) a compound of formula I in free form;

(3) a compound of formula I wherein the basic ring structure of Aconsists of a ring having 5 or 6 ring members to which a further ringhaving 5 or 6 ring members may have been fused, especially of a ringhaving 5 or 6, preferably 6, ring members;

(4) a compound of formula I wherein the basic ring structure of A isunsaturated and contains especially from 1 to 4, preferably from 2 to 4,double bonds, preferably conjugated double bonds, and is especially ofaromatic character;

(5) a compound of formula I wherein the basic ring structure of Acontains 1, 2 or 3 hetero atoms selected from the group consisting ofoxygen, sulfur and nitrogen, not more than one of the hetero atoms inthe basic ring structure being an oxygen atom and not more than one ofthe hetero atoms in the basic ring structure being a sulfur atom,especially 1 or 2 hetero atoms selected from the group consisting ofoxygen, sulfur and nitrogen, not more than one of the hetero atoms inthe basic ring structure being an oxygen atom or a sulfur atom,preferably a nitrogen atom;

(6) a compound of formula I wherein A is selected from the group ofheterocycles consisting of ##STR6## wherein E is C₁ -C₃ alkyl and Q ishydrogen, C₁ -C₃ alkyl or cyclopropyl, or, where appropriate, a tautomerthereof;

(7) a compound of formula I wherein A is bonded via a carbon atom of itsbasic ring structure to the remainder of the compound of formula I;

(8) a compound of formula I wherein A is unsubstituted or mono- ordi-substituted by substituents selected from the group consisting ofhalogen, --OH, --SH, C₁ -C₃ alkyl, halo-C₁ -C₃ alkyl, C₁ -C₃ alkoxy andhalo-C₁ -C₃ aloxy, and a ring nitrogen atom of A may have been replacedby ##STR7## preferably unsubstituted or mono- or di-substituted bysubstituents selected from the group consisting of halogen and C₁ -C₃alkyl, and a ring nitrogen atom of A may have been replaced by ##STR8##especially mono-substituted by halogen, more especially mono-substitutedby chlorine;

(9) a compound of formula I wherein A is pyridyl, 1-oxidopyridinio orthiazolyl each of which may be unsubstituted or substituted,

preferably pyrid-3-yl, 1-oxido-3-pyridinio or thiazol-5-yl, each ofwhich may be unsubstituted or substituted,

especially pyrid-3-yl, 2-halopyrid-5-yl, 2,3-dihalopyrid-5-yl, 2-(C₁ -C₃alkyl)pyrid-5-yl, 1-oxido-3-pyridinio, 2-halo-1-oxido-5-pyridinio,2,3-dihalo-1-oxido-5-pyridinio or 2-halo-thiazol-5-yl,

more especially pyrid-3-yl, 2-halopyrid-5-yl, 2-halo-1-oxido-5-pyridinioor 2-halothiazol-5-yl,

preferably 2-chloropyrid-5-yl, 2-methylpyrid-5-yl, 1-oxido-3-pyridinio,2-chloro-1-oxido-5-pyridinio, 2,3-dichloro-1-oxido-5-pyridinio or2-chlorothiazol-5-yl,

especially pyrid-3-yl, 2-chloropyrid-5-yl, 2-chloro-1-oxido-5-pyridinioor 2-chlorothiazol-5-yl,

more especially 2-chlorothiazol-5-yl or 2-chloropyrid-5-yl,

most especially 2-chloropyrid-5-yl;

(10) a compound of formula I wherein R₁ is hydrogen or methyl,especially hydrogen;

(11) a compound of formula I wherein R₂ is hydrogen or methyl,especially hydrogen;

(12) a compound of formula I wherein

R₃ is hydrogen, C₁ -C₆ alkyl, halo-C₁ -C₆ alkyl, C₁ -C₆ alkoxy-C₁ -C₆alkyl, phenoxy-C₁ -C₆ alkyl, benzyloxy-C₁ -C₆ alkyl, di(C₁ -C₄alkyl)amino-C₁ -C₆ alkyl, cyano-C₁ -C₆ alkyl, C₁ -C₄ alkylcarbonyl-C₁-C₆ alkyl, C₁ -C₄ alkoxycarbonyl-C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₂ -C₆alkenyl, C₂ -C₆ alkynyl, C(═O)--C₁ -C₄ alkyl, C(═O)--O--C₁ -C₄ -alkyl orN(R₆)₂ and

each R₆, independently of the other, is hydrogen, C₁ -C₄ alkyl orphenyl;

R₃ being especially hydrogen, C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₃ -C₄alkenyl or C₃ -C₄ alkynyl, preferably hydrogen, C₁ -C₄ alkyl or C₃ -C₆cycloalkyl, especially hydrogen or C₁ -C₄ alkyl, preferably methyl;

(13) a compound of formula I wherein X is CH--NO₂ ;

(14) a compound of formula I wherein X is N--CN;

(15) a compound of formula I wherein n is 1 or 2, especially 1;

(16) a compound of formula I wherein

A is a pyridyl, 1-oxidopyridinio or thiazolyl group bonded via a carbonatom of its basic ring structure to the remainder of the compound offormula I and unsubstituted or mono- or di-substituted by substituentsselected from the group consisting of halogen and C₁ -C₃ alkyl,

R₁ and R₂ are each independently of the other hydrogen or methyl,

R₃ is hydrogen, C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₃ -C₄ alkenyl or C₃ C₄alkynyl,

n is 1 or 2 and

X is CH--NO₂ or N--CN;

(17) a compound of formula I wherein

A is pyrid-3-yl, 2-chloropyrid-5-yl, 1-oxido-3-pyridinio,2-chloro-1-oxido-5-pyridinio, 2,3-dichloro-1-oxido-5-pyridinio or2chlorothiazol-5-yl,

R₁ and R₂ are each independently of the other hydrogen or methyl,

R₃ is hydrogen or C₁ -C₄ alkyl,

n is 1 or 2 and

X is CH--NO₂ or N--CN;

(18) a compound of formula I wherein

A is 2-chlorothiazol-5-yl or 2-chloropyrid-5-yl,

R₁ and R₂ are hydrogen,

R₃ is hydrogen or C₁ -C₄ alkyl,

n is 1 or 2 and

X is CH--NO₂ ;

(19) a compound of formula I wherein

A is 2-chlorothiazol-5-yl or 2-chloropyrid-5-yl,

R₁ and R₂ are hydrogen,

R₃ is hydrogen or C₁ -C₄ alkyl,

n is 1 or 2 and

X is N--CN;

(20) a compound of formula I wherein

A is 2-chlorothiazol-5-yl or 2-chloropyrid-5-yl,

R₁ and R₂ are hydrogen,

R₃ is hydrogen or C₁ -C₄ alkyl,

n is 1 or 2 and

X is N--NO₂.

Within the scope of the invention, special preference is given to thecompounds of formula I mentioned in Examples P15, P18 and P19.

Within the scope of the invention, preference is given specifically to:

(a)3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-nitromethylidene-pyrrolidine,

(b) 3-(2-chloropyrid-5-yl-methyl)-2-nitromethylidene-pyrrolidine,

(c)3-(2-chlorothiazol-5-yl-methyl)-1-methyl-2-nitromethylidene-pyrrolidine,

(d) 3-(2-chlorothiazol-5-yl-methyl)-2-nitromethylidene-pyrrolidine,

(e)3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-nitromethylidene-piperidine,

(f) 3-(2-chloropyrid-5-yl-methyl)-2-nitromethylidene-piperidine,

(g)3-(2-chlorothiazol-5-yl-methyl)-1-methyl-2-nitromethylidene-piperidine,

(h) 3-(2-chlorothiazol-5-yl-methyl)-2-nitromethylidene-piperidine,

(i) 3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-cyanimino-pyrrolidine,

(k) 3-(2-chloropyrid-5-yl-methyl)-2-cyanimino-pyrrolidine,

(l) 3-(2-chlorothiazol-5-yl-methyl)-1-methyl-2-cyanimino-pyrrolidine,

(m) 3-(2-chlorothiazol-5-yl-methyl)-2-cyanimino-pyrrolidine,

(n) 3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-cyanimino-piperidine,

(o) 3-(2-chloropyrid-5-yl-methyl)-2-cyanimino-piperidine,

(p) 3-(2-chlorothiazol-5-yl-methyl)-1-methyl-2-cyanimino-piperidine and

(q) 3-(2-chlorothiazol-5-yl-methyl)-2-cyaniminopiperidine.

The invention relates further to a process for the preparation of acompound of formula I which comprises either reacting

a) a compound of formula ##STR9## wherein A, R₁, R₂ and n are as definedabove for formula I and R₄ is C₁ -C₆ alkyl, or a tautomer and/or a saltthereof, or

b) for the preparation of a compound of formula I wherein R₃ is otherthan hydrogen, a salt of formula ##STR10## wherein A, R₁, R₂ and n areas defined above for formula I, R₃₃ has the definitions given for R₃ informula I with the exception of hydrogen, R₄ is C₁ -C₆ alkyl and Y⁻ is acounter ion, preferably a halide or a sulfate, or, where appropriate, atautomer thereof, or

c) a compound of formula ##STR11## wherein A, R₁, R₂, R₃ and n are asdefined above for formula I, or a tautomer and/or a salt thereof,

with nitromethane, cyanamide, a salt of nitromethane or of cyanamide,where appropriate in the presence of a base, or with ammonia and anitration reagent, where appropriate in the presence of an acid, or

d) for the preparation of a compound of formula I wherein R₃ is otherthan hydrogen, reacting a compound of formula ##STR12## (obtainable, forexample, in accordance with process a) or c)), wherein A, R₁, R₂, X andn are as defined above for formula I, or a salt thereof, with a compoundof formula

    Y--R.sub.33                                                (IV),

wherein R₃₃ has the definitions given for R₃ in formula I with theexception of hydrogen, and Y is a leaving group,

and/or, if desired, converting a compound of formula I obtainable inaccordance with the process or by another method, or a tautomer thereof,in each case in free form or in salt form, into a different compound offormula I or a tautomer thereof, separating a mixture of isomersobtainable in accordance with the process and isolating the desiredisomer and/or converting a free compound of formula I obtainable inaccordance with the process or by another method, or a tautomer thereof,into a salt or converting a salt of a compound of formula I obtainablein accordance with the process or by another method, or a tautomerthereof, into the free compound of formula I or an isomer or tautomerthereof or into a different salt

The present invention relates also to a process for the preparation of acompound of formula IIa, or a salt thereof, which comprises

e) reacting a compound of formula ##STR13## wherein A, R₁, R₂ and n areas defined above for formula I, or a salt thereof, with a compound offormula

    Y--R.sub.4                                                 (V),

wherein R₄ is C₁ -C₆ calkyl and Y is a leaving group, preferably in thepresence of a base.

The compounds of formula IIa, the salts thereof and, where appropriate,the tautomers thereof and the salts of those tautomers are novel and thepresent invention relates also thereto.

The present invention relates further to a process for the preparationof a salt of formula IIb or, where appropriate, a tautomer thereof,which comprises

f) reacting a compound of formula ##STR14## wherein A, R₁, R₂ and n areas defined above for formula I and R₃₃ has the definitions given for R₃in formula I with the exception of hydrogen, or a salt thereof, with acompound of formula (V), where appropriate in the presence of a base.

The salts of formula IIb and, where appropriate, the tautomers thereofare novel and the present invention relates also thereto.

The present invention relates further to a process for the preparationof a compound of formula III or, where appropriate, a tautomer thereof,in each case in free form or in salt form, which comprises

g) reacting a compound of formula ##STR15## wherein A, R₁, R₂, R₃ and nare as defined above for formula III, or a salt thereof, with athionating agent.

The compounds of formula III and the tautomers thereof, in each case infree form or in salt form, are novel and the invention relates alsothereto.

The present invention relates further to a process for the preparationof a compound of formula VI or, where appropriate, a tautomer thereof,in each case in free form or in salt form, which comprises

h) reacting a compound of formula ##STR16## wherein A and R₁ are asdefined above for formula I and Y is a leaving group, with a compound offormula ##STR17## wherein R₂ and n are as defined above for formula Iand R₃₃₃ has the definitions given above for R₃ in formula I with theexception of hydrogen or is a protecting group, or a salt thereof, andwhere appropriate, if desired,

i) converting a compound of formula ##STR18## (obtainable by thatprocess or by another method), wherein A, R₁, R₂ and n are as definedabove for formula I, or a tautomer and/or a salt thereof, with acompound of formula

    Y--R.sub.33                                                (IV),

wherein R₃₃ is as defined for formula IIb and Y is a leaving group, intoa compound of formula ##STR19## wherein A, R₁, R₂ and n are as definedabove for formula I and R₃₃ has the definitions given for R₃ in formulaIIb, or into a salt thereof

The compounds of formula VI, in free form or in salt form, and, whereappropriate, the tautomers thereof, in free form or in salt form, arenovel and the invention relates also thereto.

The starting materials of formulae IV, V, VII and VIII referred tohereinbefore and hereinafter, which are used for the preparation of thecompounds of formulae I, II, III and VI or, where appropriate, thetautomeric compounds thereof, in each case in free form or in salt form,are known or can be prepared in accordance with methods known per se.

The remarks made above in relation to the isomers and tautomers and/orthe salts of compounds of formula I applies in analogous manner to thestarting materials and intermediates of formulae II to VIII referred tohereinbefore and hereinafter as regards the possible tautomers and tothe isomers and, where appropriate, the tautomers and/or the saltsthereof.

The reactions of Variants a) to i) described hereinbefore andhereinafter are carried out in a manner known per se, for example in theabsence or, customarily, the presence of a suitable solvent or diluentor of a mixture thereof, the reaction being carried out as required withcooling, at room temperature or with heating, for example in atemperature range of approximately from -120° C. to the boilingtemperature of the reaction mixture, preferably from approximately -80°C. to approximately +150° C., and, if necessary, in a closed vessel,under pressure, in an inert gas atmosphere and/or under anhydrousconditions. Especially advantageous reaction conditions are to be foundin the Examples.

Variants a, b and c):

The reactants can be reacted with one another as such, i.e. without theaddition of a solvent or diluent, or, preferably, in the presence of asolvent or diluent. The following may be mentioned as examples of suchsolvents and diluents:

aromatic, aliphatic and alicyclic hydrocarbons and halogenatedhydrocarbons, such as benzene, toluene, xylene, mesitylene, tetralin,chlorobenzene, dichlorobenzene, bromobenzene, petroleum ether, hexane,cyclohexane, dichloromethane, trichloromethane, tetrachloromethane,dichloroethane, trichloroethene or tetrachloroethene; ethers, such asdiethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether,tert-butyl methyl ether, ethylene glycol monomethyl ether, ethyleneglycol monoethyl ether, ethylene glycol dimethyl ether, dimethoxydiethylether, tetrahydrofuran or dioxane; alcohols, such as methanol, ethanol,propanol, isopropanol, butanol, ethylene glycol or glycerol; amides,such as N,N-dimethylformamide, N,N-diethylformamide,N,N-dimethylacetamide, N-methylpyrrolidone or hexamethylphosphoric acidtriamide; nitriles, such as acetonitrile or propionitrile; andsulfoxides, such as dimethylsulfoxide.

Examples of suitable bases for facilitating the reaction withnitromethane or cyanamide are alkali metal or alkaline earth metalhydroxides, hydrides, amides, alkanolates, acetates, carbonates,dialkylamides or alkylsilylamides, or alkylamines, alkylenediamines,unsubstituted or N-alkylated, saturated or unsaturated cycloalkylamines,basic heterocycles, ammonium hydroxides and carbocyclic amines. Theremay be mentioned by way of example sodium hydroxide, hydride, amide,methanolate, acetate or carbonate, potassium tert-butanolate, hydroxide,carbonate or hydride, lithium diisopropylamide, potassiumbis(trimethylsilyl)amide, calcium hydride, triethylamine,diisopropylethylamine, triethylenediamine, cyclohexylamine,N-cyclohexyl-N,N-dimethylamine, N,N-diethylaniline, pyridine,4-(N,N-dimethylamino)pyridine, quinuclidine, N-methylmorpholine,benzyl-trimethylammonium hydroxide and1,5-diazabicyclo[5.4.0]undec-5-ene (DBU).

In a further variant, the reaction can be carried out with a metal saltof nitromethane or cyanamide. The alkali metal salts of nitromethane orcyanamide, especially the sodium salts, are especially suitable. Thebases mentioned above are suitable for the preparation of the salts fromfree nitromethane or cyanamide.

Suitable as nitration agents for the reaction of a compound of formulaII or III with ammonia and a nitration agent are the reagentscustomarily used for such reactions, such as nitric acid, N₂ O₃, N₂ O₄,N₂ O₅, alkali metal nitrates, such as KNO₃ or NaNO₃, AgNO₃, alkylnitrates, such as ethyl or butyl nitrate, and nitronium salts, such asNO₂ BF₄ or NO₂ CF₃ SO₃, especially nitric acid.

In the nitration reactions according to the invention, it is preferableto add the customary acids, that is to say, for example, sulfuric acid,perchloric acid, methanesulfonic acid, trifluoromethanesulfonic acid orphosphoric acid. Special preference is given, however, to a process inwhich nitric acid is used for the nitration.

A further preferred form of Variant b) comprises adding to the reactionmixture a precipitating agent for the anion, such as silver carbonate orbarium chloride.

The reaction is advantageously carried out in a temperature range fromapproximately 0° C. to approximately +200° C., preferably fromapproximately +10° C. to approximately +140° C., and in many cases inthe range from room temperature to the reflux temperature of thereaction mixture.

Variant d:

The reactants can be reacted with one another as such, i.e. without theaddition of a solvent or diluent, for example in the melt. Generally,however, the addition of an inert solvent or diluent or of a mixturethereof is advantageous. Examples of such solvents or diluents are, forexample, the same as those mentioned for Variants a) to c).

Suitable leaving groups Y in the compounds of formulae IV, V and VIIIare, for example, hydroxy, C₁ -C₈ alkoxy, halo-C₁ -C₈ alkoxy, C₁ -C₈alkanoyloxy, mercapto, C₁ -C₈ alkylthio, halo-C₁ -C₈ alkylthio, C₁ -C₈alkanesulfonyloxy, halo-C₁ -C₈ alkanesulfonyloxy, benzenesulfonyloxy,toluenesulfonyloxy, sulfate and halogen, especially toluenesulfonyloxy,trifluoromethylsulfonyloxy, sulfate and halogen, more especiallysulfate, chlorine, bromine and iodine.

Suitable bases for facilitating the H-Y removal are, for example, thoseof the type indicated for Variants a) to c).

The reaction is advantageously carried out in a temperature range offrom approximately -100° C. to approximately +180° C., preferably fromapproximately -100° C. to approximately +130° C., and in many cases inthe range from room temperature to the reflux temperature of thereaction mixture.

Variants e and f):

The reactants can be reacted with one another as such, i.e. without theaddition of a solvent or diluent, for example in the melt. Generally,however, the addition of an inert solvent or diluent or of a mixturethereof is advantageous. Suitable solvents or diluents are, for example,those of the type mentioned for Variants a) to c).

The reaction is advantageously carried out in a temperature range offrom approximately -20° C. to approximately +160° C., preferably from 0°C. to +120° C., and in many cases at the reflux temperature of thereaction mixture.

Suitable bases for facilitating the H-Y removal are, for example, thoseof the type indicated for Variant a).

Suitable leaving groups Y in the compounds of formula V are, forexample, those of the type indicated for Variant d).

Variant g):

The reactants can be reacted with one another as such, i.e. without theaddition of a solvent or diluent, for example in the melt. Generally,however, the addition of an inert solvent or diluent or of a mixturethereof is advantageous. Suitable solvents or diluents are, for example,those of the type mentioned for Variants a) to c).

The reaction is preferably carried out in a temperature range of from 0°C. to +200° C., preferably at from room temperature to +150° C.

Suitable thionating agents are, for example, O,O-diethyldithiophosphoricacid, B₂ S₃, B₂ S₅, phosphorus pentasulfide and Lawesson's reagent[2,4-bis(4methoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-disulfide].

Variant h):

The reactants can be reacted with one another as such, i.e. without theaddition of a solvent or diluent, for example in the melt. Generally,however, the addition of an inert solvent or diluent or of a mixturethereof is advantageous. Suitable solvents or diluents are, for example,those of the type mentioned for Variants a) to c).

The reaction is preferably carried out in a temperature range of from-120° C. to +100° C., preferably at from -80° C. to +60° C., andpreferably in the presence of a base. Suitable bases for the H-Y removalare, for example, those of the type mentioned for synthesis Variants a)to c). Suitable leaving groups Y are the groups indicated for synthesisVariant d), especially halogen.

When R₃ in the compound of formula VI to be prepared is hydrogen, R₃₃₃in the compound of formula VII must be a protecting group. Suitableprotecting groups are those that are customarily used, such as acyl,trialkylsilyl, such as trimethylsilyl, or alkyl, such as tert-butyl,which can be removed again, if necessary, in a further synthesis step.

Variant i):

The same conditions as those mentioned for Variant d) apply.

Salts of compounds of formulae I, II, III and VI can be prepared in amanner known per se. For example, acid addition salts are obtained bytreatment with a suitable acid or a suitable ion exchange reagent, andsalts with bases are obtained by treatment with a suitable base or asuitable ion exchange reagent.

Salts of compounds of formulae I, II, III and VI can be converted intothe free compounds of formulae I, II, III and VI in customary manner:acid addition salts, for example, by treatment with a suitable basicagent or a suitable ion exchange reagent, and salts with bases, forexample, by treatment with a suitable acid or a suitable ion exchangereagent.

Salts of compounds of formulae I, II, III and VI can be converted intodifferent salts of compounds of formulae I, II, III and VI in a mannerknown per se: acid addition salts, for example, can be converted intodifferent acid addition salts, for example by treatment of a salt of aninorganic acid, such as a hydrochloride, with a suitable metal salt,such as a sodium, barium or silver salt, of an acid, for example withsilver acetate, in a suitable solvent in which an inorganic salt beingformed, for example silver chloride, is insoluble and therefore iseliminated from the reaction mixture.

Depending upon the procedure and the reaction conditions, compounds offormulae I, II, III and VI having salt-forming properties can beobtained in free form or in the form of salts.

The compounds of formulae I, II, III and VI and, where appropriate,their tautomers, in each case in free form or in salt form, may be inthe form of one of the possible isomers or as a mixture thereof, forexample according to the number of asymmetric carbon atoms occurring inthe molecule and the absolute and relative configuration thereof and/oraccording to the configuration of non-aromatic double bonds occurring inthe molecule, they may be in the form of pure isomers, such as antipodesand/or diastereoisomers, or in the form of mixtures of isomers, such asmixtures of enantiomers, for example racemates, mixtures ofdiastereoisomers or mixtures of racemates; the invention relates both tothe pure isomers and to all possible mixtures of isomers and this is tobe understood hereinbefore and hereinafter, even when stereochemicaldetails are not specifically mentioned in each case.

Mixtures of diastereoisomers and mixtures of racemates of compounds offormulae I, II, III and VI, or their salts, that are obtainable inaccordance with the process, depending upon the starting materials andprocedures chosen, or by another method, can be separated into the purediastereoisomers or racemates in known manner on the basis of thephysico-chemical differences between the constituents, for example byfractional crystallisation, distillation and/or chromatography.

Mixtures of enantiomers, such as racemates, so obtainable can beseparated into the optical antipodes by known methods, for example byrecrystallisation from an optically active solvent, by chromatography onchiral adsorbents, for example high-pressure liquid chromatography(HPLC) on acetyl cellulose, with the aid of suitable microorganisms, bycleavage with specific immobilised enzymes, via the formation ofinclusion compounds, for example using chiral crown ethers, in whichcase only one enantiomer is complexed, or by conversion intodiastereoisomeric salts, for example by reaction of a basic end productracemate with an optically active acid, such as a carboxylic acid, forexample camphoric, tartaric or malic acid, or sulfonic acid, for examplecamphorsulfonic acid, and separation of the resulting mixture ofdiastereoisomers, for example on the basis of their differentsolubilities by fractional crystallisation, into the diastereoisomersfrom which the desired enantiomer can be freed by the action ofsuitable, for example basic, agents.

Apart from by the separation of corresponding mixtures of isomers, it ispossible according to the invention to obtain pure diastereoisomers orenantiomers also by generally known methods of diastereoselective orenantioselective synthesis, for example by carrying out the processaccording to the invention with starting materials having suitablestereochemistry.

It is advantageous to isolate or synthesise the biologically more activeisomer, for example enantiomer or diastereoisomer, or mixture ofisomers, for example mixture of enantiomers or mixture ofdiastereoisomers, insofar as the individual components have differentbiological activity.

The compounds of formulae I, II, III and VI and their salts can also beobtained in the form of their hydrates and/or may include othersolvents, for example solvents that may be used for the crystallisationof compounds in solid form.

The invention relates to all those forms of the process according towhich a compound obtainable as starting material or intermediate at anystage of the process is used as starting material and all or some of theremaining steps are carried out, or a starting material is used in theform of a derivative or a salt and/or its racemates or antipodes or,especially, is formed under the reaction conditions.

Compounds of formula I obtainable in accordance with the process or byanother method can be converted in a manner known per se into differentcompounds of formula I.

In particular, for example, compounds of formulae I, II, III, VI and VIIhaving heterocyclic radicals A that contain a nitrogen atom as heteroatom, can be converted by oxidation into the desired N-oxides, or theradicals A can be halogenated.

In the process of the present invention there are preferably used thosestarting materials and intermediates, in each case in free form or insalt form, which result in the compounds of formula I described at thebeginning as being especially valuable, or their salts.

The invention relates especially to the preparation processes describedin Examples P1 to P19.

In the area of pest control, the compounds of formula I according to theinvention are valuable preventive and/or curative active ingredientshaving a very advantageous biocidal spectrum even at low rates ofconcentration, while being well tolerated by warm-blooded animals, fishand plants. The compounds of the invention are effective against all orindividual development stages of normally sensitive animal pests, butalso of resistant animal pests, such as insects. The insecticidal actionof the compounds of the invention may manifest itself directly, i.e. inthe mortality of the pests, which occurs immediately or only after sometime, for example during moulting, or indirectly, for example in reducedoviposition and/or hatching rate, good activity corresponding to amortality of at least 50 to 60%.

The mentioned animal pests include, for example:

of the order Lepidoptera, for example,

Acleris spp., Adoxophyes spp., Aegeria spp., Agrotis spp., Alabamaargillaceae, Amylois spp., Anticarsia gemmatalis, Archips spp.,Argyrotaenia spp., Autographa spp., Busseola fusca, Cadra cautella,Carposina nipponensis, Chilo spp., Choristoneura spp., Clysiaambiguella, Cnaphalocrocis spp., Cnephasia spp., Cochylis spp.,Coleophora spp., Crocidolomia binotalis, Cryptophlebia leucotreta, Cydiaspp., Diatraea spp., Diparopsis castanea, Earias spp., Ephestia spp.,Eucosma spp., Eupoecilia ambiguella, Euproctis spp., Euxoa spp.,Grapholita spp., Hedya nubiferana, Heliothis spp., Hellula undalis,Hyphantria cunea, Keiferia lycopersicella, Leucoptera scitella,Lithocollethis spp., Lobesia botrana, Lymantria spp., Lyonetia spp.,Malacosoma spp., Mamestra brassicae, Manduca sexta, Operophtera spp.,Ostrinia nubilalis, Pammene spp., Pandemis spp., Panolis flammea,Pectinophora gossypiella, Phthorimaea operculella, Pieris rapae, Pierisspp., Plutella xylostella, Prays spp., Scirpophaga spp., Sesamia spp.,Sparganothis spp., Spodoptera spp., Synanthedon spp., Thaumetopoea spp.,Tortrix spp., Trichoplusia ni and Yponomeuta spp.;

of the order Coleoptera, for example,

Agriotes spp., Anthonomus spp., Atomaria linearis, Chaetocnema tibialis,Cosmopolites spp., Curculio spp., Dermestes spp., Diabrotica spp.,Epilachna spp., Eremnus spp., Leptinotarsa decemlineata, Lissorhoptrusspp., Melolontha spp., Orycaephilus spp., Otiorhynchus spp., Phlyctinusspp., Poplllia spp., Psyriodes spp., Rhizopertha spp., Scarabeidae,Sitophilus spp., Sitotroga spp., Tenebiio spp., Tribolium spp. andTrogoderma spp.;

of the order Orthoptera, for example,

Blatta spp., Blattella spp., Gryllotalpa spp., Leucophaea maderae,Locusta spp., Periplaneta spp. and Schistocerca spp.;

of the order Isoptera, for example,

Reticulitermes spp.;

of the order Psocoptera, for example,

Liposcelis spp.;

of the order Anoplura, for example,

Haematopinus spp., Linognathus spp., Pediculus spp., Pemphigus spp. andPhylloxera spp.;

of the order Mallophaga, for example,

Damalinea spp. and Trichodectes spp.;

of the order Thysanoptera, for example,

Frankliniella spp., Hercinothrips spp., Taeniothrips spp., Thrips palmi,Thrips tabaci and Scirtothrips aurantii;

of the order Heteroptera, for example,

Cimex spp., Distantiella theobroma, Dysdercus spp., Euchistus spp.,Eurygaster spp., Leptocorisa spp., Nezara spp., Piesma spp., Rhodniusspp., Sahlbergella singularis, Scotinophara spp. and Triatoma spp.;

of the order Homoptera, for example,

Aleurothrixus floccosus, Aleyrodes brassicae, Aonidiella spp.,Aphididae, Aphis spp., Aspidiotus spp., Bemisia tabaci, Ceroplasterspp., Chrysomphalus aonidium, Chrysomphalus dictyospermi, Coccushesperidum, Empoasca spp., Eriosoma larigerum, Erythroneura spp.,Gascardia spp., Laodelphax spp., Lecanium corni, Lepidosaphes spp.,Macrosiphus spp., Myzus spp., Nephotettix spp., Nilaparvata spp.,Paratoria spp., Pemphigus spp., Planococcus spp., Pseudaulacaspis spp.,Pseudococcus spp., Psylla spp., Pulvinaria aethiopica, Quadraspidiotusspp., Rhopalosiphum spp., Saissetia spp., Scaphoideus spp., Schizaphisspp., Sitobion spp., Trialeurodes vaporariorum, Trioza erytreae andUnaspis citri;

of the order Hymenoptera, for example,

Acromyrmex, Atta spp., Cephus spp., Diprion spp., Diprionidae, Gilpiniapolytoma, Hoplocampa spp., Lasius spp., Monomorium pharaonis, Neodiprionspp., Solenopsis spp. and Vespa spp.;

of the order Diptera, for example,

Aedes spp., Antherigona soccata, Bibio hortulanus, Calliphoraerythrocephala, Ceratitis spp., Chrysomyia spp., Culex spp., Cuterebraspp., Dacus spp., Drosophila melanogaster, Fannia spp., Gastrophilusspp., Glossina spp., Hypoderma spp., Hyppobosca spp., Liriomyza spp.,Lucilia spp., Melanagromyza spp., Musca spp., Oestrus spp., Orseoliaspp., Oscinella frit, Pegomyia hyoscyami, Phorbia spp., Rhagoletispomonefla, Sciara spp., Stomoxys spp., Tabanus spp., Tannia spp. andTipula spp.;

of the order Siphonaptera, for example

Ceratophyllus spp. and Xenopsylla cheopis, and

of the order Thysanura, for example,

Lepisma saccharina.

With the compounds according to the invention it is possible to control,i.e. to inhibit or destroy, pests of the mentioned type occurringespecially on plants, especially on useful plants and ornamentals inagriculture, in horticulture and in forestry, or on parts of suchplants, such as the fruit, blossom, leaves, stems, tubers or roots,while some of the parts of the plants which grow later are alsoprotected against those pests.

Target crops are especially cereals, such as wheat, barley, rye, oats,rice, maize and sorghum; beet, such as sugar beet and fodder beet;fruit, such as pomes, stone fruit and soft fruit, such as apples, pears,plums, peaches, almonds, cherries, or berries, for example strawberries,raspberries or blackberries; leguminous plants, such as beans, lentils,peas and soybeans; oil plants, such as rape, mustard, poppy, olives,sunflowers, coconut, castor oil plants, cocoa beans and groundnuts;cucumber plants, such as marrows, cucumbers and melons; fibre plants,such as cotton, flax, hemp and jute; citrus fruit, such as oranges,lemons, grapefruit and mandarins; vegetables, such as spinach, lettuce,asparagus, cabbages, carrots, onions, tomatoes, potatoes and paprika;lauraceae, such as avocados, cinnamon and camphor; and tobacco, nuts,coffee, aubergines, sugar cane, tea, pepper, vines, hops, bananas andnatural rubber plants, as well as ornamentals.

The compounds of the invention are suitable especially for controllingAphis craccivora, Bemisia tabaci, Heliothis virescens, Myzus persicae,Nephotettix cincticeps and Nilaparvata lugens in vegetable, fruit, riceand soybean crops.

Further areas of use of the compounds according to the invention are theprotection of stored goods and stocks and materials, and also in thehygiene sector, especially the protection of domestic animals andproductive livestock against pests of the mentioned type.

The invention therefore relates also to pesticides, such as emulsifiableconcentrates, suspension concentrates, directly sprayable or dilutablesolutions, coatable pastes, dilute emulsions, wettable powders, solublepowders, dispersible powders, wettable powders, dusts, granules orencapsulations in polymer substances, comprising--at least--one of thecompounds of the invention, the type of formulation being chosen inaccordance with the intended objectives and prevailing circumstances.

The active ingredient is used in those compositions in pure form, asolid active ingredient, for example, in a specific particle size, orpreferably together with--at least--one of the adjuvants customary informulation technology, such as extenders, for example solvents or solidcarriers, or surface-active compounds (surfactants).

Suitable solvents are, for example: optionally partially hydrogenatedaromatic hydrocarbons, preferably the fractions of alkylbenzenescontaining 8 to 12 carbon atoms, such as xylene mixtures, alkylatednaphthalenes or tetrahydronaphthalene, aliphatic or cycloaliphatichydrocarbons, such as paraffins or cyclohexane, alcohols, such asethanol, propanol or butanol, glycols and their ethers and esters, suchas propylene glycol, dipropylene glycol ether, ethylene glycol orethylene glycol monomethyl or monoethyl ether, ketones, such ascyclohexanone, isophorone or diacetone alcohol, strongly polar solvents,such as N-methylpyrtolid-2-one, dimethyl sulfoxide orN,N-dimethylformamide, water, vegetable oils or epoxidised vegetableoils, such as rape oil, castor oil, coconut oil or soybean oil orepoxidised rape oil, castor oil, coconut oil or soybean oil, andsilicone oils.

The solid carriers used, e.g. for dusts and dispersible powders, arenormally natural mineral fillers such as calcite, talcum, kaolin,montmorillonite or attapulgite. In order to improve the physicalproperties it is also possible to add highly dispersed silicic acids orhighly dispersed absorbent polymers. Suitable granulated adsorptivecarriers are porous types, such as pumice, broken brick, sepiolite orbentonite; and suitable nonsorbent carriers are calcite or sand. Inaddition, a great number of granulated materials of inorganic or organicnature can be used, especially dolomite or pulverised plant residues.

Depending on the nature of the compound to be formulated, suitablesurface-active compounds are non-ionic, cationic and/or anionicsurfactants or mixtures of surfactants having good emulsifying,dispersing and wetting properties. The surfactants listed below are tobe regarded merely as examples; many more surfactants customarilyemployed in formulation technology and suitable for use according to theinvention are described in the relevant literature.

Non-ionic surfactants are preferably polyglycol ether derivatives ofaliphatic or cycloaliphatic alcohols, saturated or unsaturated fattyacids and alkylphenols, said derivatives containing 3 to 30 glycol ethergroups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon moietyand 6 to 18 carbon atoms in the alkyl moiety of the alkylphenols.Further suitable non-ionic surfactants are water-soluble adducts ofpolyethylene oxide with polypropylene glycol,ethylenediaminopolypropylene glycol and alkylpolypropylene glycolcontaining 1 to 10 carbon atoms in the alkyl chain, which adductscontain 20 to 250 ethylene glycol ether groups and 10 to 100 propyleneglycol ether groups. These compounds usually contain 1 to 5 ethyleneglycol units per propylene glycol unit. Representative examples ofnon-ionic surfactants are nonylphenol polyethoxyethanols, castor oilpolyglycol ethers, polypropylene/polyethylene oxide adducts,tributylphenoxypolyethoxyethanol, polyethylene glycol andoctylphenoxypolyethoxyethanol. Fatty acid esters of polyoxyethylenesorbitan, e.g. polyoxyethylene sorbitan trioleate, are also suitablenon-ionic surfactants.

Cationic surfactants are preferably quaternary ammonium salts whichcontain, as substituent, at least one C₈ -C₂₂ alkyl radical and, asfurther substituents, unsubstituted or halogenated lower alkyl, benzylor hydroxy-lower alkyl radicals. The salts are preferably in the form ofhalides, methyl sulfates or ethyl sulfates. An example isstearyltrimethylammonium chloride.

Both water-soluble soaps and water-soluble synthetic surface-activecompounds are suitable anionic surfactants. Suitable soaps are thealkali metal salts, alkaline earth metal salts and unsubstituted orsubstituted ammonium salts of higher fatty acids (C₁₀ -C₂₂), e.g. thesodium or potassium salts of oleic or stearic acid or of natural fattyacid mixtures which can be obtained e.g. from coconut oil or tall oil;mention may also be made of fatty acid methyltaurin salts. Morefrequently, however, synthetic surfactants are used, especially fattysulfonates, fatty sulfates, sulfonated benzimidazole derivatives oralkylarylsulfonates. The fatty sulfonates or sulfates are usually in theform of alkali metal salts, alkaline earth metal salts or unsubstitutedor substituted ammonium salts and generally contain a C₈ -C₂₂ alkylradical, which also includes the alkyl moiety of acyl radicals; theremay be mentioned by way of example the sodium or calcium salt oflignosulfonic acid, of dodecyl sulfate or of a mixture of fatty alcoholsulfates obtained from natural fatty acids. These compounds alsocomprise the salts of sulfated and sulfonated fatty alcohol/ethyleneoxide adducts. The sulfonated benzimidazole derivatives preferablycontain 2 sulfonic acid groups and one fatty acid radical containingapproximately 8 to 22 carbon atoms. Examples of alkylarylsulfonates arethe sodium, calcium or triethanolammonium salts ofdodecylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid or of acondensate of naphthalenesulfonic acid and formaldehyde. Also suitableare corresponding phosphates, e.g. salts of the phosphoric acid ester ofan adduct of p-nonylphenol with 4 to 14 mol of ethylene oxide, orphospholipids.

The compositions usually comprise 0.1 to 99%, preferably 0.1 to 95%, ofactive ingredient, and 1 to 99.9%, preferably 5 to 99.9%, of--atleast--one solid or liquid adjuvant, it generally being possible for 0to 25%, preferably 0.1 to 20%, of the composition to be surfactants (ineach case percentages are by weight). Whereas commercial products willpreferably be formulated as concentrates, the end user will normallyemploy dilute formulations which have considerably lower activeingredient concentrations. Preferred formulations have especially thefollowing composition (throughout, percentages are by weight):

    ______________________________________                                        Emulsifiable concentrates:                                                      active ingredient: 1 to 90%, preferably 5 to 50%                              surfactant: 1 to 30%, preferably 10 to 50%                                    solvent: 5 to 98%, preferably 70 to 85%                                       Dusts:                                                                        active ingredient: 0.1 to 10%, preferably 0.1 to 5%                           solid carrier: 99.9 to 90%, preferably 99.9 to 99%                            Suspension concentrates:                                                      active ingredient: 5 to 75%, preferably 10 to 50%                             water: 94 to 24%, preferably 88 to 30%                                        surfactant: 1 to 40%, preferably 2 to 30%                                     Wettable powders:                                                             active ingredient: 0.5 to 90%, preferably 1 to 80%                            surfactant: 0.5 to 20%, preferably 1 to 15%                                   solid carrier: 5 to 99%, preferably 15 to 98%                                 Granules:                                                                     active ingredient; 0.5 to 30%, preferably 3 to 15%                            solid carrier: 99.5 to 70%, preferably 97 to 85%                            ______________________________________                                    

The activity of the compositions according to the invention can besubstantially broadened and adapted to prevailing circumstances by theaddition of other insecticidal active ingredients. Examples of suitableadditional active ingredients include representatives of the followingclasses of compounds: organophosphorus compounds, nitrophenols andderivatives, formamidines, ureas, carbamates, pyrethroids, chlorinatedhydrocarbons, and Bacillus thuringiensis preparations. The compositionsaccording to the invention may also comprise further solid or liquidadjuvants, such as stabilisers, for example vegetable oils or epoxidisedvegetable oils (e.g. epoxidised coconut oil, rape oil or soybean oil),antifoams, for example silicone oil, preservatives, viscosityregulators, binders and/or tackifiers, as well as fertilisers or otheractive ingredients for obtaining special effects, for exampleacaricides, bactericides, fungicides, nematicides, molluscicides orselective herbicides.

The compositions according to the invention are prepared in knownmanner, in the absence of adjuvants, for example by grinding, sievingand/or compressing a solid active ingredient or mixture of activeingredients, for example to a specific particle size, and in thepresence of at least one adjuvant, for example by intimately mixingand/or grinding the active ingredient or mixture of active ingredientswith the adjuvant(s). The invention relates also to those processes forthe preparation of the compositions according to the invention and tothe use of the compounds of formula I for the preparation of thosecompositions.

The invention relates also to the methods of application of thecompositions, i.e. the methods of controlling pests of the mentionedtype, such as spraying, atomising, dusting, coating, dressing,scattering or pouring, which are selected in accordance with theintended objectives and prevailing circumstances, and to the use of thecompositions for controlling pests of the mentioned type. Typical ratesof concentration are from 0.1 to 1000 ppm, preferably from 0.1 to 500ppm, of active ingredient The rates of application per hectare aregenerally from 1 to 2000 g of active ingredient per hectare, especiallyfrom 10 to 1000 g/ha, preferably from 20 to 600 g/ha.

A preferred method of application in the area of plant protection isapplication to the foliage of the plants (foliar application), thenumber of applications and the rate of application depending on the riskof infestation by the pest in question. However, the active ingredientcan also penetrate the plants through the roots (systemic action) if thelocus of the plants is impregnated with a liquid formulation or if theactive ingredient is incorporated in solid form into the locus of theplants, for example into the soil, e.g. in granular form (soilapplication). In paddy rice crops, such granules may be applied inmetered amounts to the flooded rice field.

The compositions according to the invention are also suitable forprotecting plant propagation material, e.g. seed material, such asfruit, tubers or grains, or plant cuttings, from animal pests. Thepropagation material can be treated with the formulation beforeplanting: seed, for example, can be dressed before being sown. Thecompounds of the invention can also be applied to grains (coating),either by impregnating the grains with a liquid formulation or bycoating them with a solid formulation. The formulation can also beapplied to the planting site when the propagation material is beingplanted, for example to the seed furrow during sowing. The inventionrelates also to those methods of treating plant propagation material andto the plant propagation material thus treated.

The following Examples are intended to illustrate the invention and donot limit the invention. Ratios of solvents are given in parts byvolume.

PREPARATION EXAMPLES Example P1:3-(2-Chloropyrid-5-yl-methyl)-pyrrolid-2-one ##STR20##

Under a nitrogen atmosphere at a temperature of from -78° C. to -60° C.,180 ml of a 1.5 molar solution of lithium diisopropylamide (LDA) incyclohexane are added dropwise to 31.4 g ofN-trimethylsilylpyrrolid-2-one in 150 ml of tetrahydrofuran (THF) andthe reaction mixture is stirred at the same temperature for a furtherone hour. Then, at from -78° C. to -60° C., 25.5 g of2-chloro-5-chloromethylpyridine in 40 ml of THF are added, and themixture is stirred for a further 16 hours at that temperature and thenfor a further three hours at room temperature. The reaction mixture ispoured onto a mixture of ice/water and extracted with ethyl acetate, andthe organic phase is separated off. The ethyl acetate phase is driedover sodium sulfate and concentrated to dryness by evaporation in vacuo.The residue is purified on silica gel using ethyl acetate/hexane (7:1)as eluant. The title compound having a melting point of 117-118° C.(compound 1.3) is obtained.

Example P2: 3-(2-Chloropyrid-5-yl-methyl)-1-methyl-pyrrolid-2-one##STR21##

Under an argon atmosphere at a temperature of from -78° C. to -60° C.,150 ml of a 1.5 molar solution of lithium diisopropylamide (LDA) incyclohexane are added dropwise in the course of one hour to 20 g ofN-methylpyrrolid-2-one in 50 ml of tetrahydrofuran (THF) and thereaction mixture is stirred at the same temperature for a further onehour. Then, at from -78° C. to -60° C., 25.0 g of2chloro-5-(chloromethyl)-pyridine in 40 ml of THF are added, and themixture is stirred for a further 6 hours at that temperature and thenfor a further 6 hours at 0° C. 15 ml of methanol are added and thereaction mixture is then poured onto a mixture of ice/water andextracted with ethyl acetate, and the organic phase is separated off.The ethyl acetate phase is dried over magnesium sulfate and concentratedto dryness by evaporation in vacuo. The residue is purified on silicagel using ethyl acetate/hexane (7:1) as eluant. The title compound(compound 1.4) is obtained in the form of a colourless oil.

Example P3

The other compounds listed in Table 1 can be prepared in a manneranalogous to that described in Examples P1 and P2.

                  TABLE 1                                                         ______________________________________                                        Compounds of the formula                                                        #STR22##                                                                       -                                                                          Comp.                                                                           No. A n R.sub.1 R.sub.2 R.sub.3 Phys. data                                  ______________________________________                                        1.1   pyrid-3-yl  1     H    H    H                                             1.2 pyrid-3-yl 1 H H CH.sub.3                                                 1.3 2-Cl-pyrid-5-yl 1 H H H m.p. 117-118° C.                           1.4 2-Cl-pyrid-5-yl 1 H H CH.sub.3 oil                                        1.5 2-Cl-thiazol-5-yl 1 H H H                                                 1.6 2-Cl-thiazol-5-yl 1 H H CH.sub.3                                          1.7 pyrid-3-yl 2 H H H                                                        1.8 pyrid-3-yl 2 H H CH.sub.3                                                 1.9 2-Cl-pyrid-5-yl 2 H H H m.p. 129-130° C.                           1.10 2-Cl-pyrid-5-yl 2 H H CH.sub.3                                           1.11 2-Cl-thiazol-5-yl 2 H H H                                                1.12 2-Cl-thiazol-5-yl 2 H H CH.sub.3                                       ______________________________________                                    

Example P4: 3-(2-Chloropyrid-5-yl-methyl)-pyrrolide-2-thione ##STR23##

A mixture of 1.0 g of 3-(2-chloropyrid-5-yl-methyl)-pyrrolid-2-one and0.96 g of Lawesson's reagent[2,4-bis(4-methoxyphenyl)-1,3-dithia-2,4-diphosphetane 2,4-di-sulfide]in 15 ml of toluene is boiled at reflux for 15 minutes. After removal ofthe solvent, the residue is purified on silica gel using ethylacetate/hexane (6:1) as eluant. The title compound having a meltingpoint of 151-152° C. (compound 2.3) is obtained.

Example P5: 3-(2-Chloropyrid-5-yl-methyl)-1-methyl-pyrrolide-2-thione##STR24##

A mixture of 10 g of3-(2-chloropyrid-5-yl-methyl)-1-methyl-pyrrolid-2-one and 9 g ofLawesson's reagent in 40 ml of toluene is boiled at reflux for 15minutes. After removal of the solvent, the residue is purified on silicagel using ethyl acetatelhexane (6:1) as eluant. The title compound isobtained in the form of a yellowish solid having a melting point of44-47° C. (compound 2.4).

Example P6

The other compounds listed in Table 2 can be prepared in a manneranalogous to that described in Examples P4 and P5.

                  TABLE 2                                                         ______________________________________                                        Compounds of the formula                                                        #STR25##                                                                       -                                                                          Comp.                                                                           No. A n R.sub.1 R.sub.2 R.sub.3 Phys. data                                  ______________________________________                                        2.1   pyrid-3-yl  1     H    H    H                                             2.2 pyrid-3-yl 1 H H CH.sub.3                                                 2.3 2-Cl-pyrid-5-yl 1 H H H m.p. 151-152° C.                           2.4 2-Cl-pyrid-5-yl 1 H H CH.sub.3 m.p. 44-47° C.                      2.5 2-Cl-thiazol-5-yl 1 H H H                                                 2.6 2-Cl-thiazol-5-yl 1 H H CH.sub.3                                          2.7 pyrid-3-yl 2 H H H                                                        2.8 pyrid-3-yl 2 H H CH.sub.3                                                 2.9 2-Cl-pyrid-5-yl 2 H H H m.p. 162-163° C.                           2.10 2-Cl-pyrid-5-yl 2 H H CH.sub.3                                           2.11 2-Cl-thiazol-5-yl 2 H H H                                                2.12 2-Cl-thiazol-5-yl 2 H H CH.sub.3                                       ______________________________________                                    

Example P7: 3-(2-Chloropyrid-5-yl-methyl)-2-methylthio-1-azacyclopentene##STR26##

0.6 g of 3-(2-chloropyrid-5-yl-methyl)-pyrrolide-2-thione are added to amixture of 0.1 g of sodium hydride (50% in oil) and 10 ml ofdimethylformamide. The mixture is stirred for 20 minutes at roomtemperature and then 0.38 g of methyl iodide is added. The reactionmixture is stirred for a further 30 minutes at room temperature, pouredonto ice-water and extracted with ethyl acetate. The organic phase isdried over magnesium sulfate and concentrated to dryness by evaporationin vacuo. The title compound is obtained in the form of an oil (compound3.2).

Example P8

The other compounds listed in Table 3 can be prepared in a manneranalogous to that described in Example P7.

                  TABLE 3                                                         ______________________________________                                        Compounds of the formula                                                        #STR27##                                                                       -                                                                          Comp.                                                                           No. A n R.sub.1 R.sub.2 R.sub.4 Phys. data                                  ______________________________________                                        3.1   pyrid-3-yl  1      H    H    CH.sub.3                                     3.2 2-Cl-pyrid-5-yl 1 H H CH.sub.3 oil                                        3.3 2-Cl-pyrid-5-yl 1 H H C.sub.2 H.sub.5                                     3.4 2-Cl-thiazol-5-yl 1 H H CH.sub.3                                          3.5 pyrid-3-yl 2 H H CH.sub.3                                                 3.6 2-Cl-pyrid-5-yl 2 H H CH.sub.3 oil                                        3.7 2-Cl-pyrid-5-yl 2 H H C.sub.2 H.sub.5                                     3.8 2-Cl-thiazol-5-yl 2 H H CH.sub.3                                        ______________________________________                                    

Example P9:3-(2-Chloropyrid-5-yl-methyl)-1-methyl-2-methylthio-1-azacyclopentenyliumiodide ##STR28##

A mixture of 5.0 g of3-(2-chloropyrid-5-yl-methyl)-1-methyl-pyrrolide-2-thione and 3 g ofmethyl iodide is maintained at 40° C. for four hours without stirring.The excess methyl iodide is removed in vacuo. The title compound havinga melting point of 144-147° C. (compound 4.2) is obtained.

Example P10

The other compounds listed in Table 4 can be prepared in a manneranalogous to that described in Example P9.

                                      TABLE 4                                     __________________________________________________________________________    Compounds of the formula                                                        #STR29##                                                                       -                                                                          Comp.                                                                           No. A n R.sub.1 R.sub.2 R.sub.3 R.sub.4 Y Phys. data                        __________________________________________________________________________    4.1 pyrid-3-yl                                                                            1  H  H  CH.sub.3                                                                         CH.sub.3                                                                          I                                                   4.2 2-Cl-pyrid-5-yl 1 H H CH.sub.3 CH.sub.3 I m.p. 144-147° C.                                       4.3 2-Cl-pyrid-5-yl 1 H H CH.sub.3                                           C.sub.2 H.sub.5 I                                4.4 2-Cl-thiazol-5-yl 1 H H CH.sub.3 CH.sub.3 I                               4.5 pyrid-3-yl 2 H H CH.sub.3 CH.sub.3 I                                      4.6 2-Cl-pyrid-5-yl 2 H H CH.sub.3 CH.sub.3 I                                 4.7 2-Cl-pyrid-5-yl 2 H H CH.sub.3 C.sub.2 H.sub.5 I                          4.8 2-Cl-thiazol-5-yl 2 H H CH.sub.3 CH.sub.3 I                             __________________________________________________________________________

Example P11:3-(2-Chloropyrid-5-yl-methyl)-2-nitromethylidene-pyrrolidine ##STR30##

A mixture of 0.4 g of3-(2-chloropyrid-5-yl-methyl)-2-methylthio-1-azacyclopent-1-ene and 10ml of nitromethane is stirred at reflux temperature for five days. Themixture is concentrated by evaporation in vacuo and the residue ispurified on silica gel using dichloromethanetmethanol (95:5) as eluant.The title compound having a melting point of 159-160° C. is obtained(compound 5.3).

Example P12:3-(2-Chloropyrid-5-yl-methyl)-1-methyl-2-nitromethylidene-pyrrolidine##STR31##

A mixture of 4.0 g of3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-methylthio-1-azacyclopent-1-enyliumiodide, 4.0 g of potassium carbonate and 40 ml of nitromethane is heatedat 100° C. for 15 minutes. The mixture is concentrated to dryness byevaporation and the residue is chromatographed on silica gel using ethylacetate as eluant. The title compound having a melting point of 141-142°C. is obtained (compound 5.4).

Example P13:3-(2-Chloropyrid-5-yl-methyl)-1-methyl-2-nitromethylidene-pyrrolidine

A mixture of 3-(2-chloropyrid-5-yl-methyl)-1-methyl-pyrrolide-2-thione,0.12 g of silver carbonate and 3 ml of nitromethane is stirred at refluxfor one hour. The mixture is concentrated by evaporation in vacuo andthe crude product is chromatographed on silica gel with ethyl acetate.The title compound having a melting point of 141-142° C. (compound 5.4)is obtained.

Example P14:3-(2-Chloropyrid-5-yl-methyl)-1-ethyl-2-nitromethylidene-pyrrolidine##STR32##

A mixture of 0.5 g of3-(2-chloropyrid-5-yl-methyl)-2-nitromethylidene-pyrrolidine, 0.3 g ofethyl iodide and 0.27 g of potassium carbonate in 3 ml ofdimethylformamide is stirred at room temperature for 18 hours. Thereaction mixture is poured onto water and extracted with diethyl ether.The ether phase is dried over magnesium sulfate and concentrated byevaporation in vacuo. The residue is chromatographed on silica gel withethyl acetate/hexane (2:1). The title compound having a melting point of129-131° C. (compound 5.5) is obtained.

Example P15

The other compounds listed in Table 5 can be prepared in a manneranalogous to that described in Examples P11 to P14.

                                      TABLE 5                                     __________________________________________________________________________    Compounds of the formula                                                        #STR33##                                                                       -                                                                          Comp.                          m.p.                                             No. A n R.sub.1 R R.sub.3 (° C.)                                     __________________________________________________________________________    5.1 pyrid-3-yl                                                                             1  H   H   H                                                       5.2 pyrid-3-yl 1 H H CH.sub.3                                                 5.3 2-Cl-pyrid-5-yl 1 H H H 159-161° C.                                5.4 2-Cl-pyrid-5-yl 1 H H CH.sub.3 141-142° C.                         5.5 2-Cl-pyrid-5-yl 1 H H C.sub.2 H.sub.5 129-131° C.                  5.6 2-Cl-pyrid-5-yl 1 H H C.sub.3 H.sub.7 -n 128-129° C.                                             5.7 2-Cl-pyrid-5-yl 1 H H CH.sub.2                                           CH═CH.sub.2 116-117° C.                                             5.8 2-Cl-pyrid-5-yl 1 H H CH.sub.2                                           C.tbd.CH                                         5.9 2-Cl-pyrid-5-yl 1 H H C.sub.4 H.sub.9 -n                                  5.10 2-Cl-thiazol-5-yl 1 H H H                                                5.11 2-Cl-thiazol-5-yl 1 H H CH.sub.3                                         5.12 2-Cl-pyrid-5-yl 1 CH.sub.3 H H                                           5.13 2-Cl-pyrid-5-yl 1 H CH.sub.3 H                                           5.14 pyrid-3-yl 2 H H H                                                       5.15 pyrid-3-yl 2 H H CH.sub.3                                                5.16 2-Cl-pyrid-5-yl 2 H H H 179-181° C.                               5.17 2-Cl-pyrid-5-yl 2 H H CH.sub.3                                           5.18 2-Cl-pyrid-5-yl 2 H H C.sub.2 H.sub.5                                    5.19 2-Cl-pyrid-5-yl 2 H H C.sub.3 H.sub.7 -n                                 5.20 2-Cl-pyrid-5-yl 2 H H CH.sub.2 CH═CH.sub.2                           5.21 2-Cl-pyrid-5-yl 2 H H CH.sub.2 C.tbd.CH                                  5.22 2-Cl-pyrid-5-yl 2 H H C.sub.4 H.sub.9 -n                                 5.23 2-Cl-thiazol-5-yl 2 H H H                                                5.24 2-Cl-thiazol-5-yl 2 H H CH.sub.3                                         5.25 2-Cl-pyrid-5-yl 2 CH.sub.3 H H                                           5.26 2-Cl-pyrid-5-yl 2 H CH.sub.3 H                                           5.27 2-Cl-pyrid-5-yl 1 H H benzyl resin                                     __________________________________________________________________________

Example P16: 3-(2-Chloropyrid-5-yl-methyl)-2-cyanimino-pyrrolidine##STR34##

A mixture of 3.6 g of 3-(2-chloropyrid-5-yl-methyl)pyrrolide-2-thione,2.42 g of cyanamide and 30 ml of ethanol is boiled at reflux temperaturefor 90 minutes. The mixture is concentrated by evaporation in vacuo andthe residue is chromatographed on silica gel using ethylacetate/methanol (9:1) as eluant. The title compound having a meltingpoint of 137-140° C. (compound 6.3) is obtained.

Example P17:3-(2-Chloropyrid-5-yl-methyl)-1-methyl-2-cyanimino-pyrrolidine ##STR35##

A mixture of 3.7 g of3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-methylthio-1-azacyclopent-1-enyliumiodide and 2.5 g of cyanamide in 20 ml of ethanol is boiled at refluxfor 6 hours. The mixture is concentrated by evaporation in vacuo and theresidue is chromatographed on silica gel using dichloromethane/methanol(19:1) as eluant. The title compound having a melting point of 53-54° C.(compound 6.4) is obtained.

Example P18

The other compounds listed in Table 6 can be prepared in a manneranalogous to that described in Examples P16 and P17.

                                      TABLE 6                                     __________________________________________________________________________    Compounds of the formula                                                        #STR36##                                                                       -                                                                          Comp.                                                                           No. A n R.sub.1 R.sub.2 R.sub.3 Phys. data                                  __________________________________________________________________________    6.1 pyrid-3-yl                                                                            1  H   H   H                                                        6.2 pyrid-3-yl 1 H H CH.sub.3                                                 6.3 2-Cl-pyrid-5-yl 1 H H H m.p. 137-140° C.                           6.4 2-Cl-pyrid-5-yl 1 H H CH.sub.3 m.p. 53-54° C.                      6.5 2-Cl-pyrid-5-yl 1 H H C.sub.2 H.sub.5                                     6.6 2-Cl-pyrid-5-yl 1 H H C.sub.3 H.sub.7 -n                                  6.7 2-Cl-pyrid-5-yl 1 H H CH.sub.2 CH═CH.sub.2                            6.8 2-Cl-pyrid-5-yl 1 H H CH.sub.2 C.tbd.CH                                   6.9 2-Cl-pyrid-5-yl 1 H H C.sub.4 H.sub.9 -n                                  6.10 2-Cl-thiazol-5-yl 1 H H H                                                6.11 2-Cl-thiazol-5-yl 1 H H CH.sub.3                                         6.12 2-Cl-pyrid-5-yl 1 CH.sub.3 H H                                           6.13 2-Cl-pyrid-5-yl 1 H CH.sub.3 H                                           6.14 pyrid-3-yl 2 H H H                                                       6.15 pyrid-3-yl 2 H H CH.sub.3                                                6.16 2-Cl-pyrid-5-yl 2 H H H m.p. 169-171° C.                          6.17 2-Cl-pyrid-5-yl 2 H H CH.sub.3                                           6.18 2-Cl-pyrid-5-yl 2 H H C.sub.2 H.sub.5                                    6.19 2-Cl-pyrid-5-yl 2 H H C.sub.3 H.sub.7 -n                                 6.20 2-Cl-pyrid-5-yl 2 H H CH.sub.2 CH═CH.sub.2                           6.21 2-Cl-pyrid-5-yl 2 H H CH.sub.2 C.tbd.CH                                  6.22 2-Cl-pyrid-5-yl 2 H H C.sub.4 H.sub.9 -n                                 6.23 2-Cl-thiazol-5-yl 2 H H H                                                6.24 2-Cl-thiazol-5-yl 2 H H CH.sub.3                                         6.25 2-Cl-pyrid-5-yl 2 CH.sub.3 H H                                           6.26 2-Cl-pyrid-5-yl 2 H CH.sub.3 H                                           6.27 2-Cl-pyrid-5-yl 2 H CH.sub.3 benzyl                                    __________________________________________________________________________

Example P19

The compounds listed in Table 7 can be prepared in a manner analogous tothat described in Examples P1 to P18.

                  TABLE 7                                                         ______________________________________                                        Compounds of the formula                                                        #STR37##                                                                       -                                                                          Comp.                                                                           No. A n R.sub.1 R.sub.2 R.sub.3 Phys. data                                  ______________________________________                                        7.1   pyrid-3-yl  1     H   H   H                                               7.2 pyrid-3-yl 1 H H CH.sub.3                                                 7.3 2-Cl-pyrid-5-yl 1 H H H                                                   7.4 2-Cl-pyrid-5-yl 1 H H CH.sub.3                                            7.5 2-Cl-pyrid-5-yl 1 H H C.sub.2 H.sub.5                                     7.6 2-Cl-pyrid-5-yl 1 H H C.sub.3 H.sub.7 -n                                  7.7 2-Cl-pyrid-5-yl 1 H H CH.sub.2 CH═CH.sub.2                            7.8 2-Cl-pyrid-5-yl 1 H H CH.sub.2 C.tbd.CH                                   7.9 2-Cl-pyrid-5-yl 1 H H C.sub.4 H.sub.9 -n                                  7.10 2-Cl-thiazol-5-yl 1 H H H                                                7.11 2-Cl-thiazol-5-yl 1 H H CH.sub.3                                       ______________________________________                                    

Formulation Examples (throughout, percentages are by weight)

    ______________________________________                                        Example F1: Emulsifiable concentrates                                                              a)       b)     c)                                       ______________________________________                                        compound No. 1.2     25%      40%    50%                                        calcium dodecylbenzenesulfonate  5%  8%  6%                                   castor oil polyethylene glycol                                                ether (36 mol of ethylene oxide)  5% -- --                                    tributylphenol polyethylene glycol                                            ether (30 mol of ethylene oxide) -- 12%  4%                                   cyclohexanone -- 15% 20%                                                      xylene mixture 65% 25% 20%                                                  ______________________________________                                    

Emulsions of any desired concentration can be prepared from suchconcentrates by dilution with water.

    ______________________________________                                        Example F2: Solutions                                                                           a)     b)       c)   d)                                     ______________________________________                                        compound No. 1.3  80%    10%      5%   95%                                      ethylene glycol monomethyl                                                    ether 20% --  -- --                                                           polyethylene glycol -- 70% -- --                                              (mol. wt. 400)                                                                N-methyl-2-pyrrolidone -- 20% -- --                                           epoxidised coconut oil -- -- 1%  5%                                           petroleum fraction -- -- 94%  --                                              (boiling range 160-190° C.)                                          ______________________________________                                    

These solutions are suitable for application in the form of microdrops.

    ______________________________________                                        Example F3: Granules                                                                           a)     b)       c)   d)                                      ______________________________________                                        compound No. 1.2  5%    10%       8%  21%                                       kaolin 94% -- 79% 54%                                                         highly dispersed silicic acid  1% -- 13%  7%                                  attapulgite -- 90% -- 18%                                                   ______________________________________                                    

The active ingredient is dissolved in dichloromethane, the solution issprayed onto the carrier, and the solvent is subsequently evaporated offin vacuo.

    ______________________________________                                        Example F4: Dusts    a)     b)                                                ______________________________________                                        compound No. 1.2     2%     5%                                                  highly dispersed silicic acid 1% 5%                                           talcum 97%   --                                                               kaolin -- 90%                                                               ______________________________________                                    

Ready-for-use dusts are obtained by intimately mixing the carriers withthe active ingredient.

    ______________________________________                                        Example F5: Wettable powders                                                                    a)        b)     c)                                         ______________________________________                                        compound No. 1.2  25%       50%    75%                                          sodium lignosulfonate 5%  5% --                                               sodium lauryl sulfate 3% --  5%                                               sodium diisobutylnaphthalene- --  6% 10%                                      sulfonate                                                                     octylphenol polyethylene --  2% --                                            glycol ether (7-8 mol of                                                      ethylene oxide)                                                               highly dispersed silicic acid 5% 10% 10%                                      kaolin 62%  27% --                                                          ______________________________________                                    

The active ingredient is mixed with the adjuvants and the mixture isthoroughly ground in a suitable mill, affording wettable powders whichcan be diluted with water to give suspensions of any desiredconcentration.

    ______________________________________                                        Example F6: Emulsifiable concentrate                                          ______________________________________                                        compound No. 1.3       10%                                                      octylphenol polyethylene glycol ether  3%                                     (4-5 mol of ethylene oxide)                                                   calcium dodecylbenzenesulfonate  3%                                           castor oil polyglycol ether  4%                                               (36 mol of ethylene oxide)                                                    cyclohexanone 30%                                                             xylene mixture 50%                                                          ______________________________________                                    

Emulsions of any required concentration can be obtained from thisconcentrate by dilution with water.

    ______________________________________                                        Example F7: Dusts  a)     b)                                                  ______________________________________                                        compound No. 1.2    5%     8%                                                   talcum 95% --                                                                 kaolin -- 92%                                                               ______________________________________                                    

Ready-for-use dusts are obtained by mixing the active ingredient withthe carrier and grinding the mixture in a suitable mill.

    ______________________________________                                        Example F8: Extruder granules                                                 ______________________________________                                        compound No. 1.3   10%                                                          sodium lignosulfonate  2%                                                     carboxymethylcellulose  1%                                                    kaolin 87%                                                                  ______________________________________                                    

The active ingredient is mixed and ground with the adjuvants, and themixture is moistened with water. The mixture is extruded and granulated,and then dried in a stream of air.

    ______________________________________                                        Example F9: Coated granules                                                   ______________________________________                                        compound No. 1.2     3%                                                         polyethylene glycol (mol. wt. 200) 3%                                         kaolin 94%                                                                  ______________________________________                                    

The finely ground active ingredient is uniformly applied, in a mixer, tothe kaolin moistened with polyethylene glycol. Non-dusty coated granulesare obtained in this manner.

    ______________________________________                                        Example F10: Suspension concentrate                                           ______________________________________                                        compound No. 1.3          40%                                                   ethylene glycol 10%                                                           nonylphenol polyethylene glycol ether 6%                                      (15 mol of ethylene oxide)                                                    sodium lignosulfonate 10%                                                     carboxymethylcellulose 1%                                                     37% aqueous formaldehyde solution 0.2%                                        silicone oil in the form of a 75% 0.8%                                        aqueous emulsion                                                              water 32%                                                                   ______________________________________                                    

The finely ground active ingredient is intimately mixed with theadjuvants, giving a suspension concentrate from which suspensions of anydesired concentration can be obtained by dilution with water.

Biological Examples (throughout, percentages are by weight, unlessotherwise indicated) Example B1: Action against Anthonomus grandis

Young cotton plants are sprayed with an aqueous emulsion comprising 400ppm of test compound. After the spray coating has dried, the plants arepopulated with 10 Anthonomus grandis adults and placed in a plasticscontainer. Evaluation is made 3 days later. The percentage reduction inthe population and the percentage reduction in feeding damage (%activity) are determined by comparing the number of dead beetles and thefeeding damage on the treated plants with that on untreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3, 5.4, 5.6 and 5.7 are more than 80% effective.

Example B2: Action against Aphis craccivora

Pea seedlings are infested with Aphis craccivora, then sprayed with aspray mixture comprising 400 ppm of test compound and then incubated at20° C. Evaluation is made 3 to 7 days later. The percentage reduction inthe population (% activity) is determined by comparing the number ofdead Aphis craccivora individuals on the treated plants with that onuntreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compound 5.3 is more than 80% effective.

Example B3: Action against Bemisia tabaci

Dwarf bean plants are placed in gauze cages and populated with adults ofBemisia tabaci. After oviposition, all the adults are removed. 10 dayslater the plants, with the Bemisia tabaci nymphs on them, are sprayedwith an aqueous emulsion comprising 400 ppm of test compound. After afurther 14 days, the percentage hatching rate of the eggs is evaluatedin comparison with untreated control batches.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3, 5.4 and 5.6 are more than 80% effective.

Example B4: Systemic action against Ctenocephalides felis

20 adult fleas of the Ctenocephalides felis species are placed in a flatround cage closed on both sides with gauze. A vessel sealed on theunderside with a parafilm membrane is placed on the cage. The vesselcontains blood comprising 50 ppm of test compound and maintained at aconstant 37°. The fleas ingest the blood through the membrane.Evaluation is made 24 and 48 hours after the start of the test. Thepercentage reduction in the population (% activity) is determined bycomparing the number of dead Ctenocephalides felis fleas when treatedblood is used with that when untreated blood is used. The blood isreplaced by fresh treated blood 24 hours after treatment.

Compounds of Tables 5 to 7 exhibit good activity in this test Inparticular, compound 5.3 is more than 80% effective.

Example B5: Action against Diabrotica balteata

Maize seedlings are sprayed with an aqueous emulsion comprising 400 ppmof test compound. After the spray coating has dried, the seedlings arepopulated with 10 Diabrotica balteata larvae in the second stage andplaced in a plastics container. Evaluation is made 6 days later. Thepercentage reduction in the population (% activity) is determined bycomparing the number of dead larvae on the treated plants with that onuntreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3 to 5.7 and 5.16 are more than 80% effective.

Example B6: Action against Heliothis virescens

Young soybean plants are sprayed with an aqueous emulsion comprising 400ppm of test compound. After the spray coating has dried, the plants arepopulated with 10 Heliothis virescens caterpillars in the first stageand placed in a plastics container. Evaluation is made 6 days later. Thepercentage reduction in the population and the percentage reduction infeeding damage (% activity) are determined by comparing the number ofdead caterpillars and the feeding damage on the treated plants with thaton untreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compound 5.3 is more than 80% effective.

Example B7: Ovo/larvicidal action against Heliothis virescens

Egg deposits of Heliothis virescens on cotton are sprayed with anaqueous emulsion comprising 400 ppm of test compound. 8 days later, thepercentage of eggs which have hatched and the survival rate of thecaterpillars are evaluated in comparison with untreated controls (%reduction in the population).

Compounds of Tables 5 to 7 exhibit good activity in this test.

Example B8: Action against Myzus persicae

Pea seedlings are infested with Myzus persicae, then sprayed with aspray mixture comprising 400 ppm of test compound and then incubated at20°. Evaluation is made 3 to 7 days later. The percentage reduction inthe population (% activity) is determined by comparing the number ofdead aphids on the treated plants with that on untreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this tesl Inparticular, compounds 5.3, 5.4, 5.6 and 5.16 are more than 80%effective.

Example B9: Systemic action against Myzus persicae

Pea seedlings are infested with Myzus persicae, then placed with theirroots in a spray mixture comprising 400 ppm of test compound and thenincubated at 20° C. Evaluation is made 3 to 7 days later. The percentagereduction in the population (% activity) is determined by comparing thenumber of dead aphids on the treated plants with that on untreatedplants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3, 5.4 and 5.6 are more than 80% effective.

Example B10: Action against Nephotettix cincticeps

Rice plants are sprayed with an aqueous emulsion comprising 400 ppm oftest compound. After the spray coating has dried, the plants arepopulated with Nephotettix cincticeps larvae in the 2nd and 3rd stages.Evaluation is made 21 days later. The percentage reduction in thepopulation (% activity) is determined by comparing the number ofsurviving leaf hoppers on the treated plants with that on untreatedplants.

Compounds of Tables 5 to 7 exhibit good activity in this tesl Inparticular, compounds 5.3, 5.4, 5.5 and 5.7 are more than 80% effective.

Example B11: Systemic action against Nephotettix cincticeps

Pots containing rice plants are placed in an aqueous emulsion solutioncomprising 400 ppm of test compound. The rice plants are then populatedwith Nephotettix cincticeps larvae in the 2nd and 3rd stages. Evaluationis made 6 days later. The percentage reduction in the population (%activity) is determined by comparing the number of leaf hoppers on thetreated plants with that on untreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3, 5.4, 5.6, 5.7, 5.16 and 6.4 are more than 80%effective.

Example B12: Action against Nilaparvata lugens

Rice plants are sprayed with an aqueous emulsion comprising 400 ppm oftest compound. After the spray coating has dried, the rice plants arepopulated with Nilaparvata lugens larvae in the 2nd and 3rd stages.Evaluation is made 21 days later. The percentage reduction in thepopulation (% activity) is determined by comparing the number ofsurviving plant hoppers on the treated plants with that on untreatedplants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3, 5.4 and 5.7 are more than 80% effective.

Example B13: Systemic action against Nilaparvata lugens

Pots containing rice plants are placed in an aqueous emulsion solutioncomprising 10 ppm of test compound. The plants are then populated withNilaparvata lugens larvae in the 2nd and 3rd stages. Evaluation is made6 days later. The percentage reduction in the population (% activity) isdetermined by comparing the number of plant hoppers on the treatedplants with that on untreated plants.

Compounds of Tables 5 to 7 exhibit good activity in this test. Inparticular, compounds 5.3, 5.4, 5.6, 5.7, 5.16 and 6.4 are more than 80%effective.

Example B14: Action against Spodoptera littoralis caterpillars

Young soybean plants are sprayed with an aqueous emulsion comprising 400ppm of test compound. After the spray coating has dried, the soybeanplants are populated with 10 Spodoptera littoralis caterpillars in thethird stage and placed in a plastics container. Evaluation is made 3days later. The percentage reduction in the population and thepercentage reduction in feeding damage (% activity) are determined bycomparing the number of dead caterpillars and the feeding damage on thetreated plants with that on untreated plants. Compounds of Tables 5 to 7exhibit good activity against Spodoptera littoralis in this test. Inparticular, compounds 5.3 to 5.7 are more than 80% effective.

Example B15: Action against Plutella xylostella caterpillars

Young cabbage plants are sprayed with an aqueous emulsion comprising 400ppm of test compound. After the spray coating has dried, the cabbageplants are populated with 10 Plutela xylostella caterpillars in thethird stage and placed in a plastics container. Evaluation is made 3days later. The percentage reduction in the population and thepercentage reduction in feeding damage (% activity) are determined bycomparing the number of dead caterpillars and the feeding damage on thetreated plants with that on untreated plants.

Compounds of Tables 5 to 7 exhibit good activity against Plutellaxylostella in this test In particular, compound 5.3 is more than 80%effective.

What is claimed is:
 1. A compound of formula ##STR38## wherein A is anunsubstituted or substituted heterocyclic radical selected from thegroup consisting of ##STR39## wherein a ring nitrogen atom may have beenreplaced by a group ##STR40## E is C₁ -C₃ alky; R₁ is hydrogen or C₁ -C₃alkyl;R₂ is hydrogen or C₁ -C₃ alkyl; R₃ is hydrogen, an unsubstitutedor substituted C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₂ -C₆ alkenyl or C₂ -C₆alkynyl group, or C(═O)--R₅, R₅ is C₁ -C₄ alkyl, C₁ -C₄ alkoxy, anunsubstituted or substituted phenyl, phenoxy or benzyloxy group, orN(R₆)₂, each R₆, independently of the other, is hydrogen, C₁ -C₄ alkylor unsubstituted or substituted phenyl, X is CH--NO₂, N--CN or N--NO₂and n is 1,in free form or in salt form, or, where appropriate, atautomer of such a compound or a salt thereof.
 2. A compound accordingto claim 1 of formula I, whereinA is an unsubstituted or mono- totetra-substituted heterocyclic radical wherein a ring nitrogen atom mayhave been replaced by a group ##STR41## and wherein one or two of thesubstituents of A may be selected each independently of any other fromthe group consisting of C₁ -C₃ alkyl, halo-C₁ -C₃ alkyl, cyclopropyl,halocyclopropyl, C₂ -C₃ alkenyl, C₂ -C₃ alkynyl, halo-C₂ -C₃ alkenyl,halo-C₂ -C₃ alkynyl, hydroxy, mercapto, halo-C₁ -C₃ alkoxy, C₁ -C₃alkylthio, halo-C₁ -C₃ alkylthio, allyloxy, propargyloxy, allylthio,propargylthio, haloallyloxy, haloallylthio, cyano and nitro, and fromone to four of the substituents of A may be selected each independentlyof any other(s) from the group consisting of C₁ -C₃ alkyl, C₁ -C₃ alkoxyand halogen; R₃ is hydrogen, C₁ -C₆ alkyl, halo-C₁ -C₆ alkyl, C₁ -C₆alkoxy-C₁ -C₆ alkyl, C₁ -C₆ alkyl-thio-C₁ -C₆ alkyl, phenoxy-C₁ -C₆alkyl, phenylthio-C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl-C₁ -C₆ alkyl,benzyloxy-C₁ -C₆ alkyl, di(C₁ -C₄ alkyl)amino-C₁ -C₆ alkyl, cyano-C₁ -C₆alkyl, C₁ -C₄ alkylcarbonyl-C₁ -C₆ alkyl, C₁ -C₄ alkoxycarbonyl-C₁ -C₆alkyl, C₃ -C₆ cycloalkyl, halo-C₃ -C₆ cycloalkyl, C₂ -C₆ alkenyl,halo-C₂ -C₆ alkenyl, C₂ -C₆ alkynyl, halo-C₂ -C₆ alkynyl or C(═O)--R₅,and R₅ is C₁ -C₄ alkyl, C₁ -C₄ alkoxy, phenyl, phenoxy or benzyloxy, orphenyl, phenoxy or benzyloxy substituted by from one to threesubstituents selected each independently of any other(s) from the groupconsisting of halogen, C₁ -C₄ alkyl, halo-C₁ -C₄ alkyl, C₁ -C₄ alkoxy,nitro and cyano, or is N(R₆)₂, each R₆, independently of the other, ishydrogen, C₁ -C₄ alkyl or phenyl, or phenyl substituted by from one tothree substituents selected each independently of any other(s) from thegroup consisting of halogen, C₁ -C₄ alkyl, halo-C₁ -C₄ alkyl, C₁ -C₄alkoxy, nitro and cyano.
 3. A compound according to claim 1 of formula Iin free form.
 4. A compound according to claim 1 of formula I wherein Ais bonded via a carbon atom of its basic ring to the carbon atom towhich the R₁ substituent is attached.
 5. A compound according to claim 1of formula I wherein A is unsubstituted or mono- or di-substituted bysubstituents selected from the group consisting of halogen, --OH, --SH,C₁ -C₃ alkyl, halo-C₁ -C₃ alkyl, C₁ -C₃ alkoxy and halo-C₁ -C₃ alkoxy,and a ring nitrogen atom of A may have been replaced by ##STR42##
 6. Acompound according to claim 1 of formula I wherein A is pyridyl or1-oxidopyridinio, each of which may be unsubstituted or substituted. 7.A compound according to claim 1 to of formula I wherein R₁ is hydrogenor methyl.
 8. A compound according to claim 1 to of formula I wherein R₂is hydrogen or methyl.
 9. A compound according to claim 1 to of formulaI wherein R₃ is hydrogen, C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₃ -C₄alkenyl or C₃ -C₄ alkynyl.
 10. A compound according to claim 1 to offormula I wherein X is CH--NO₂.
 11. A compound according to claim 1 toof formula I wherein X is N--CN.
 12. A compound according to claim 1 offormula I wherein A is a pyridyl or 1-oxidopyridinio group bonded via acarbon atom of it basic ring to the carbon atom to which the R₁substituent is attached and unsubstituted or mono- or di-substituted bysubstituents selected from the group consisting of ha logen and C₁ -C₃alkyl,R₁ and R₂ are each independently of the other hydrogen or methyl,R₃ is hydrogen, C₁ -C₆ alkyl, C₃ -C₆ cycloalkyl, C₃ -C₄ alkenyl or C₃-C₄ alkynyl, and X is CH--NO₂ or N--CN.
 13. A compound according toclaim 12 of formula I whereinA is pyrid-3-yl, 2-chloropyrid-5-yl,1-oxido-3-pyridinio, 2-chloro-1-oxido-5-pyridinio or2,3-dichloro-1-oxido-5-pyridinio and R₃ is hydrogen or C₁ -C₄ alkyl. 14.A compound according to claim 12 of formula I whereinA is2-chloropyrid-5-yl, R₃ is hydrogen or C₁ -C₄ alkyl and X is CH--NO₂. 15.A compound according to claim 1 of formula I selected from the groupconsisting of the followingcompounds:3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-nitromethylidene-pyrrolidine,3-(2-chloropyrid-5-yl-methyl)-2-nitromethylidene-pyrrolidine,3-(2-chloropyrid-5-yl-methyl)-1-methyl-2-cyanimino-pyrrolidine and3-(2-chloropyrid-5-yl-methyl)-2-cyanimino-pyrrolidine.
 16. A compositionfor controlling pests which comprises as active ingredient at least onecompound as described in claim 1, formula I, or, where appropriate, atautomer thereof, in each case in free form or in agrochemicallyacceptable salt form, and at least one adjuvant.
 17. A compositionaccording to claim 16 wherein the pests are insects.
 18. A method ofcontrolling plant pests, which comprises applying to the pests, or tothe locus thereof, a compound according to claim
 1. 19. A methodaccording to claim 18 wherein the pests are insects.
 20. A method ofprotecting plant propagation material against pests, which comprisestreating the propagation material or the planting site thereof with acompound according to claim
 1. 21. A process for the preparation of acompound of formula I of claim 1, which comprises either reactinga) acompound of formula ##STR43## wherein A, R₁, R₂ and n are as defamedabove for formula I and R₄ is C₁ -C₆ alkyl, or a tautomer and/or a saltthereof, or b) for the preparation of a compound of formula I wherein R₃is other than hydrogen, a salt of formula ##STR44## wherein A, R₁, R₂and n are as defined in claim 1, formula I, R₃₃ has the definitionsgiven for R₃ in claim 1, formula I, with the exception of hydrogen, R₄is C₁ -C₆ alkyl and Y⁻ is a counter ion, or, where appropriate, atautomer thereof, or c) a compound of formula ##STR45## wherein A, R₁,R₂, R₃ and n are as defined in claim 1, formula I, or a tautomer and/ora salt thereof,with nitromethane, cyanamide, a salt of nitromethane orof cyanamide or with ammonia and a nitration reagent, or d) for thepreparation of a compound of formula I wherein R₃ is other thanhydrogen, reacting a compound of formula ##STR46## wherein A, R₁, R₂, Xand n are as defined in claim 1, formula I, or a salt thereof, with acompound of formula

    Y--R.sub.33                                                (IV),

wherein R₃₃ has the definitions given for R₃ in claim 1, formula I, withthe exception of hydrogen, and Y is a leaving group.
 22. A process forthe preparation of a compound of formula ##STR47## wherein A, R₁, R₂ andn are as defined in claim 1, formula I, and R₄ is C₁ -C₆ alkyl, or,where appropriate, a tautomer thereof, in each case in free form or insalt form, which process comprisese) reacting a compound of formula##STR48## wherein A, R₁, R₂ and n are as defined in claim 1, formula I,or a salt thereof, with a compound of formula

    Y--R.sub.4                                                 (V),

wherein R₄ is C₁ -C₆ alkyl and Y is a leaving group.
 23. A compound offormula ##STR49## wherein A, R₁, R₂ and n are as defined in claim 1,formula I, and R₄ is C₁ -C₆ alkyl, or, where appropriate, a tautomerthereof, in each case in free form or in salt form.
 24. A process forthe preparation of a salt of formula ##STR50## or, where appropriate, atautomer thereof, wherein A, R₁, R₂ and n are as defined in claim 1,formula I, R₃₃ has the definitions given for R₃ in claim 1, formula I,with the exception of hydrogen, R₄ is C₁ -C₆ alkyl and Y⁻ is a counterion, which process comprisesf) reacting a compound of formula ##STR51##wherein A, R₁, R₂ and n are as defined in claim 1, formula I, and R₃₃has the definitions given for R₃ in claim 1, formula I, with theexception of hydrogen, or a salt thereof, with a compound of formula

    Y--R.sub.4                                                 (V),

wherein R₄ is C₁ -C₆ alkyl and Y⁻ is a leaving group.
 25. A salt offormula ##STR52## wherein A, R₁, R₂ and n are as defined in claim 1,formula I, R₃₃ has the definitions given for R₃ in formula I, claim 1,with the exception of hydrogen, and Y⁻ is a counter ion, or a tautomerthereof.
 26. A process for the preparation of a compound of formula##STR53## wherein A, R₁, R₂, R₃ and n are as defined in claim 1, formulaI, or, where appropriate, a tautomer thereof, in each case in free formor in salt form, which process comprisesg) reacting a compound offormula ##STR54## wherein A, R₁, R₂, R₃ and n are as defined in claim 1,formula I, or a salt thereof, with a thionating agent.
 27. A compound offormula ##STR55## wherein A, R₁, R₂, R₃ and n are as defined in claim 1,formula I, and, where appropriate, the tautomer thereof, in each case infree form or in salt form.
 28. A process for the preparation of acompound of formula ##STR56## wherein A, R₁, R₂, R₃ and n are as definedin claim 1, formula I, or, where appropriate, a tautomer thereof, ineach case in free form or in salt form, which process comprisesh)reacting a compound of formula ##STR57## wherein A and R₁ are as definedabove in claim 1, formula I, and Y is a leaving group, with a compoundof formula ##STR58## wherein R₂ and n are as defined in claim 1, formulaI, and R₃₃₃ has the definitions given for R₃ in claim 1, formula I, withthe exception of hydrogen, or is a protecting group, in free form or insalt form.
 29. A compound of formula ##STR59## wherein A, R₁, R₂, R₃ andn are as defined in claim 1, formula I, or, where appropriate, atautomer thereof, in each case in free form or in salt form.